Blast cleaning device



Sept. 19, 194.4. BOYD 2,358,557

BLAST CLEANING D EVICE Filed June 26, 1942 2 Sheets-Sheet 1 INVENTO-RS JOHN G.BoY0A/10 Cm fo/v M. HHIYE BY'WWWV AT TORN E Sept. 19,944... a BOYD HAL 2,358,557

BLAST CLEANING DEV-ICE Filed June 26. 1942 2 Sheets-Sheet 2 INVENTORS JOH G. Bax 0 AND I 'Qmff'on/ M. Hfl/YE 4 5 5M5 14 w j TTO NEY Patented Sept. 19, 1944 UNITED STATES BLAST CLEANING DEVICE John G. Boyd, Oakland, mi Clayton M.Hane, I Contra. lOosta County, Calif.

Application June 26, 1942,3611! No. 448,580 1 6 Claims.

The invention relates to a device for progressively cleaning the sides of a cylindric bore by the forcible application of a fluid against them.

A general object of the invention is to provide a particularly effective device for the cleaning of bore walls by the application of a blast of cleansing material in and along the bore.

A more specific object is to provide an improved travelling sand blast unit havingarotary head for forcibly delivering air-borne sand and similar abradants in and along the surface of a bore.

Another object is to provide a particularly simple dynamically balanced blast unit of the type described. 7 I

A-further object is to provide a particularly effective seal between the rotary head and the unit element which carries it.

An added object is to provide an improved and simple means for efiecting the rotation of the rotary head. v

The invention possesses other objects and features of advantage, some of which, with the foregoing, will be set forth or be apparent from a consideration of the following description of typical embodiments thereof and of the'accompanying drawings, in which,

Figure 1 is a. side view of a unitembo'dyingthe features of invention and operatively installed within a fragmentarily shown pipe. 7

Figure 2 is an enlarged axial section of the head end portion of the unit of'Figu're 1.

Figure 3 is a fragmentary head end view of the unit.

Figure 4 is a partly sectional axial-elevation showing alternative nozzle members installed on the rotary head of the unit. 7

Figure 5 is a sectional View taken at 5'5 in Figure 2.

Figure 6 is a fragmentary side view of a modification utilizing nozzles shown in Figure 4 fora further purpose.

Figure 7 is a front end view of the head or Figure 6.

In its present embodiments, the device of .our invention is shown as embodied in a blastingunit for use to progressively clean the surface B'bounding the uniform cylindric bore 9 of a pipe III by efiecting the forcible application of a cleaning blast to remove scale or other unwanted coatings from the bore side 8. The disclosedstru'cture has been particularly designed for the cleaning application under pressure of a continuous blast of air-borne particles which may comprise abra tic'les and/or particles of chemically active mate- "r ia'ls, as may be desirable for a bore to be cleaned. As particularly illustrated; a unit embodying the structural features of our invention essentia-llycomprises a tubular body member I I having sets of supporting and positioning legs 12 extending radially from it adjacent its ends and having the rear and front ends of its passage l3 respectively connected with'the passage of a supply =19 hose l4 and with a nozzle-supplying manifold space l5 provided within a head It rotatably mounted on the body. The hose I4 is preferably flexible, is shown as secured by screws 14' in a co'unterbore portion of the passage l3 at the rear end of the body I I, and provides a passage which is preferably of no greater diameter than the body passage whereby to avoid any constriction of the" stream at the hose connection. The hose I4 comprises the source of the pressure stream con- 20 taining' air-borne cleaning'particles for'blasting projection from the unit, and is supplied with said stream from a suitable pumping and mixing device not shown, such devices being Wll known in the art.

Split sleeves having complementary sections I! and I8 mount the legs 12 and are removably mounted on the body H for adjusted positioning therealong, bolts is being cooperative'b'etween complementary sections H and IE to olampingly 8'0 them to the body. Preferably, and as shown,

the legs I2 radiatein 'syinmetricallyspaced relatior'i' from the body axis, with the sleeve section I! providing two legs l2 While the section l8 provides but one leg |2-. Each leg 12 comprises a 85- tubular section 2| eiten'ding integrally from a sleeve section or andan outer section 22 telescopically adjustablein the bore of the section 2115i its fixing in adjusted position by a set screw 23 mounted in the outer end; of the section 2| 40 and engageable with the beam of a kerf 24 48 movement axially therealo'n'g without undue friction, and a suitable anti-friction means is preferably provided thereat, for the latter purpose, the outer portion of the section 22 may mount a: roller or'wheel 25 which has its plane constantly 50= including the unit axis to thereby minimize tread friction for a wheel engaging the surface 8. as is shown, the'portion of the section 22 which engages within the section 23 is cylindric, the engagement of theinner end of the t dants such as sand, emery or carbor'undurn' par- 66 screw 23' in the kerf 24 prevents a misalignment of the wheel during a length adjustment of a leg.

In practice, the effective lengths of the legs |2 are adjusted to substantial equality for the axially centered disposal of the unit in the pipe passage 9. When the pipe is in the prone position shown, two of the legs of each leg assembly may support the unit on wheels 24 from lower side points of the inside pipe surface 8 while the wheels of the third legs are slightly spaced from upper points of said surface as a means to prevent an appreciable tilting of the unit in the pipe passage. For the use of the unit in straight bores, the two leg assemblies are preferably positioned adjacent the opposite ends of the tubular body ll, while the use of the unit in and along curved boresmay be facilitated by decreasing the mutual spacing of the leg assemblies as permitted by the present 1eg-mounting device.

It will now be noted that the head I6 is rotatably mounted on a tubular member 26 comprising an extension of the body unitarily fixed thereto and coaxially abutting the latter with its passage 21 registering with the body passage l3 as a continuation thereof. Asparticularly shown in Figures 1 and 2 and 5, the body extension member 26 is secured to the body member H by means of a couplin sleeve 28 threadedly engaging the members, while a coupling sleeve 28' functions as the sleeve 28 for fixing the members and 25 of the embodiment of Figure 6 together as a structural element. The sectional structure thus provided for the headmounting body of the unit is designed to facilitate the assembly of the unit elements, and comprises the inm'iediate support for the rotary head It.

Intermediately thereof the body member 25 is internally stepped to provide a shoulder 29 fac ing rearwardly and against which the innerrace ring 3| of a suitable roller bearing assembly 32 engages, said race being fixedly held in its place as by its driven fit upon the member. The outer race ring 33 of the bearing assembly mounts a tubular member 34 which comprises a rear portion of the head I6 and carries a forward head member 35 providing the manifold cavity l5 which supplies the nozzles of the head with the cleaning material. As shown, the bore of the member 34 is intermediately stepped to provide a rearwardly facing shoulder 36, and its larger bore portion is arranged to closely and removably receive the race 33 in engagement with the shoulder 33 as a stop.

Rearwardly of the portion thereof which receives the race 33, the member 34 threadedly mounts within it a suitable keeper ring for releasably fixing the race 33 in place in the member and so secures the member against movement axially of the supporting body while the head r0 tates about the body axis. A radially stepped keeper ring 31 is shownin Figures 1 and 2 and provides an internal gear 381 at its rearward end portion for use in a manner to be hereinafter described, while the keeper ring3l' shown in Figure 6 lacks any gear.

Preferably, and as shown, the head member 35 includes a globate forward part 4| providing the space |5 from which the blast is discharged through suitable nozzles, and a tubular stemlike part 42 which is arranged for fixed engagement with the forward portion of the head member 34. As shown, the cylindrical part 42 is of somewhat less diameter than the globate part 4|,

threadedly engages with and within the forward portion of the member 34 while freely receiving the forward end of the body member 25, and is arranged for fixing in its mounted position by means of a lock nut 43 mounted on its threaded exterior and arranged for jambing engagement with the annular forward end of the head member 34.

Noting that the manifold cavity |5 comprises the interior space of the head member 35 provided jointly within its parts 4| and 42, and that the working pressure in said cavity is appreciably in excess of atmospheric, means are provided for preventing the pressure-forcing of the air-borne abradant into and through the bearing assembly 32. As particularly illustrated, the rearward extremity of the head member 35 is provided with an inturned flange 44 having its bore closely receiving the cylindrical exterior of the body member 26 for the rotation of the head about the member, while the portion of the head member 34 forwardly of its shoulder 36 is provided with an internal annular flange 45 having its bore receiving the body member 26 as does the flange 44. The space defined by and between the slightly beveled face at the inner end of the member 42 at its flange 44 and the flange 45, and between the exterior of the body member 25 and the interior face of the head member 34 between said flanges, comprises a stufing box which is arranged to contain a suitable soft packing 47, with the permitted adjusted setting of the head stem 42 in the member 34 determining the degree of seal provided by the packing.

To further protect the head-carrying bearings 32 from the possible movement of the abradant material thereinto by pressure, the flange 45 of the member 34 is preferably provided at a point forwardly of the shoulder 36 of the member to thereby define an annular cavity 48 between the flange and the bearing assembly, with passages 49 extending radially through the member from the'cavity. The passages 49 are constantly open and serve as relief or bleeder ducts for the space 48 to prevent the pressure circulation through th bearings of any air which may pass the packing 41. It will thus be understood that the cleaning material to be delivered in the blast from the head H5 is kept out of the support bearings for the head without interference with the rotation of the head.

In the embodiment of Figures 1 to 5 inclusive, the rotation of the head-|6 is arranged to be positively effected by driving it with a flexible shaft 5| which is actuated by a suitable motor means (not shown) and carries a pinion 52 engaging the gear 38 of the keeper 3'! for rotating the head at the desired rotary speed. In the present instance, the motor means for actuating the shaft 5| would be independent of the blast unit, and the shaft is carried in a usual flexible sheath 53 providing a head portion 54 in which a rigid shaft 55 carrying the pinion 52 and comprising the terminal portion of the shaft 5| is journalled. The appropriate positioning of the pinion 52 for engaging the gear 38 is effected by mounting the sheath head 54 on a radial extension'55 of the coupling member 28 to which it is removably secured by a bolted-on cap 51. A hanger member 58 providing an eye 59 for freely receiving the sheath '53 therethrough may be mounted at a rearward point of the body for maintaining the forward sheath and shaft portions in parallel relation to the unit axis and so prevent kinking of the sheath and shaft adjacent theshaft-mounting extension 56 of the sleeve 28.

ihgs at which suitable jet nozzles may be provided. As particularly shown, a set of openings 6| isprovided in the part 4| forwardly of the spherical center thereof, the lines of said openings radiate from said center as comprising a point in the unit axis, and said-lines makeangles of about forty five degrees with said axis and lie in a common plane including the axis whereby they are symmetrically related to the head member. A further set of two threaded openings 62 is provided in the .part 4| at opposite sides thereof and in mutually coaxial relation, with their line intersecting the unit axis at or adjacent the spherical center of the part 4|, whereby they are also symmetrically related to the head. The openings 6| and 62 are preferably of like size and threading, and screw-plugs 63 are provided for application to close tho's'e openings 6| and/or 62 not used for mounting nozzles on the head.

By particular reference to Figures 1 to 3 inclusive, it will be seen that nozzles 64 are threadedly mounted in the forward head openings 6|, said nozzles providing straight discharge passages 65 whereby these forwardly-directed passages are arranged to deliver the air-borne abradant from the head It in lines which intersect the axis of rotation of thehe'ad at a common point and make angles of substantially forty-five degrees with said-axis. With the head I'B rotating, as by the action of the drive shaft through the disclosed gear connections, while the unit is advanced through the bore to be cleaned, the jets discharged from the two nozzles 6'4will operate in helical lines along the bore surface for cleaning the latter. Although the arrangement is not shown,'it will be understood that nozzles 54 might be mounted at the rearward openings 62, with the forward openings '61 closed by screw-plugs 63 or also having nozzles 84 mounted thereat.

It may sometimes be desirable to direct the discharged jets of cleaning material rearwardly with respect to the head-part 4|, and to that end appropriately formed nozzles 66 are provided for mounting at the radial head openings 62 to PTO-v vide rearwardly directed jets of cleaning material against the surface being cleaned. As particularly brought out in Figure 4, the nozzles 66 provide curved discharge passages 61 which have their inlet and discharge ends making an angle of substantially forty-five degrees with each other. The present nozzles 64 and 66 are provided with external flanges at the bases of their threaded parts whereby they may be fixedly set against the head in operative position thereon.

With the nozzles 66 mounted to discharge rearwardly, and with the planes of their discharge passages including the head axis as in Figure 4, the flexible shaft 5| would be utilized to rotate the head l6 as before. With this nozzle arrangement, the feeding motion of the present unit in a bore to be cleaned may be one of retraction rather than of advancement with respect to the bore end from which the unit is inserted. While 'the nozzles 66 might be directed forwardly in coplanar relation with the unit axis, such a use thereof at the openings 62 in lieu of the straight nozzles 64 at the openings 6| is not generally desirable because of the added wear of an abrasive on the walls of a curved passage.

It will now be particularly noted that if the plane of the passage 61 of a mounted nozzle 66 is disposed in intersecting relation to the axis of rotation of the head IS, the line of the discharged jet does not intersect the uiiit axis and the reaction of discharge therefore produces a turning momeht' upon the head as a possible head-TOtatlIig means. jets from nozzles is provided for in the assembly Such a functioning of of Figures 6 and 7 wherein nozzles-'66 mounted at the rear openings 62 of the head IB- are disposed in symmetrical arrangement to discharge their jets obliquely forwardly for simultaneously providing the described bore-cleaning and head'- "rotating actions; a similar action may, of course,

be produced if the nozzles 66 are directed obliquely rearwardly with their planes intersectin the assembly.

While the present structures have been particularly described as for use in providing a sand blast, it will be understood that ablast of air alone may be provided by the unit, or that a liquidcleaning or coating fluid might be discharged therefrom for direction against the sides ofa bore as the unit and bore are moved relatively in the axial line of the bore; for descriptive convenience, a fluid containing an abradant may be referred to as an abradant fluid.

In the present application of the unit it is assumed that the supply hose I4 is utilized as a handle for appropriately shifting the unit in and along a bore being treated with fluid dis charged from the unit in the manners shown" "flat surfaces in front of them and transverse to the -unit axis, as well as radially within a bore.

From the foregoing description of our invention, taken in connection with the accompanying drawings, the advantages of the construction and operation will be readily understood by those skilled in the art to which the invention appertains. While we have described the features and use of assemblies which we now consider to be preferred embodiments of our invention, we desire to haveit understood that the showings are primarily illustrative, and that such changes may be made, when desired, as fall within the scope ofthe following claims.

We claim:

1. In an abradant blast unit, a rigid tubular body arranged to receive an abradant fluid under pressure, a hollow head providing a discharge nozzle and having a tubular intake portion receiving an end of the body, a ring bearing means operative between the exterior of the body and the interior of the tubular head portion for rotatably mounting the head on the body for its rotation about the axis of the body portion enclosed by it, means providing a fluidtight seal between the body and the intake portion of the head at a point between the cavity of the head and the bearing means to prevent the escape of the fluid from the head through the bearing means, and means operative to rotate the head during the discharge of fluid from the nozzle.

2. In an abradant blast unit, a tubular body arranged to receive an abradant fluid under pressure, a hollow head providing a discharge nozzle and having a tubular intake portion freely receiving an end of the body, a ring bearing means operative between the exterior of the body, and the interior of the tubular head portion for rotatably mounting the head on the body for rotation about the axis of the body portion enclosed by it, means providing a sealing ring between the body and the intake portion of the head at a point between the cavity of the head and the bearing means, said sealing ring and bearing ring being axially spaced to define an annular cavity between them and said tubular headportion being radially perforated for venting said cavity, and means to rotate the head during the discharge of fluid from the nozzle.

3. In a blast unit, a tubular body arranged to receive an abradant fluid under pressure, a hollow head rotatably mounted upon the body in sealed relation thereto for receiving the fluid therefrom and provided with a discharge opening having its line intersecting the axis of rotation of the head, a nozzle having a passage with angularly related intake and discharge portions lying in a common plane, and means adjustably mounting the nozzleat said opening for its disposition to discharge the abradant fluid in a line which is oblique to said axis of rotation in either intersecting or non-intersecting relation thereto. a 4. In a blast unit, a tubular bodyarrangedto receive an abradant fluid under pressure, a globate head rotatably mounted upon the body in sealed relation thereto for receiving the fluid therefrom and provided with a plurality of discharge openings about it in symmetrical relation to the axis of rotation of the body and having their lines meeting at a common point of the said axis, like nozzles having curved passages and mounted at said openings in position to discharge jets of the fluid in lines which are similarly oblique to said axis in such non-intersecting relation thereto that the reactions of the discharged jets are operative to urge a rotation of the head about said axis.

thereto for receiving the fluid from the body and for its rotation about a fixed axis with respect to the body and provided with a discharge opening having its line intersecting the axis or rotation of the head, a nozzle having a passage with angularly related intake and discharge portions, and means mounting the nozzle at said opening for its adjusted disposition to discharge the fluid from the head in a line whichis oblique to said axis of rotation ineither intersecting or nonintersecting relation thereto.

6. In a blast unit for progressive operation in and along a uniform bore to project a blasting fluid against the bore-defining surface, a tubular body arranged to axially receive a blasting fluid under pressure at an end thereof constituting its rear end, a hollow head swivelled upon the front body end in sealed relation thereto for receiving the fluid from the body and for its rotation about the body axis and provided with a discharg opening having its line intersecting the axis of rotation of the head, a nozzle having a passage with angularly related intake and discharge portions, means mounting the nozzle at said opening for its, adjusted disposition to discharge the fluid from the head and against said bore-defining surface in a line which is oblique to said axis of rotation in either intersecting or non-intersecting relation thereto and is directed either forwardly or rearwardly from the head, and means on the body engageable with the boredefining surface for axially centering the body in the bore for its axial movement therealong.

JOHN G. BOYD. CLAYTON M. HANE. 

